“Having established that this knowledge was in the art, the [E]xaminer could then properly rely . . . on a conclusion of obviousness ‘from common knowledge and common sense of the person of ordinary skill in the art without any specific hint or suggestion in a particular reference.’” In re Bozek, 416 F.2d 1385, 1390 (CCPA 1969). It is the Appellants’ burden to traverse the Examiner’s notice. “We did not mean to imply . . . that a bald challenge, with nothing more, would be all that was needed. . . .We feel it to be perfectly consistent with the principles governing procedural due process to require that a challenge to judicial notice by the board contain adequate information or argument so that on its face it creates a reasonable doubt regarding the circumstances justifying the judicial notice.” In re Boon, 439 F.2d 724, 728 (CCPA 1971). That has not been done here by the bald assertion that “the Examiner has erred in taking Official Notice without any substantial evidence” (App. Br. 15).